SSysLeak

Guide

Is My VPN Leaking My IP? How to Spot a WebRTC Leak

You turned the VPN on, the app says "Connected," and websites show the VPN server's location. Job done — your real IP is hidden. Except it might not be. A browser feature called WebRTC can quietly hand out your real IP address even while the VPN is running, and you'd never know from the VPN app itself.

This guide explains the leak in plain terms and how to check for it.

What WebRTC is — and why it leaks

WebRTC (Web Real-Time Communication) is built into every modern browser. It powers video calls, voice chat and peer-to-peer connections directly in the page, with no plugin. To connect two people directly, WebRTC needs to discover the network addresses each device can be reached at — so it asks the operating system for them.

That discovery process can surface IP addresses that a normal web request never would, including the real one your VPN is supposed to be masking. The site doesn't need permission, and it doesn't show a prompt. A few lines of JavaScript are enough.

Why it's so easy to miss

The leak is invisible for three reasons:

  • The VPN app still says "Connected." It's doing its job at the network layer; the leak happens inside the browser, above it.
  • Your "what's my IP" page may look fine. Ordinary page loads go through the tunnel. WebRTC takes a different path.
  • There's no error or warning. Nothing breaks. The address just... leaks.

So a VPN user can browse for months believing they're masked while every WebRTC-aware site can read their true IP.

How to tell if you're affected

A proper check compares two things:

  1. The IP address websites see from your normal connection (through the VPN).
  2. Any IP addresses WebRTC exposes.

If WebRTC surfaces an address your ordinary connection didn't — especially one tied to your real ISP or local network — that's a leak. This is exactly the "tell" that also gives away VPN users on a VPN detection test, and it's separate from browser fingerprinting, which identifies you even when no IP leaks at all.

How to fix a WebRTC leak

If you find a leak, options include:

  • Disable WebRTC in your browser settings or via a trusted extension (note it may break video calls).
  • Use a VPN or browser that blocks WebRTC leaks by default — many now do.
  • On some browsers, set WebRTC to only use the VPN's interface.

But fix only after you've confirmed there's something to fix. Run the leak test below to see, in seconds, whether your real IP is escaping through WebRTC right now.